Analytical testing apparatus.



0. C. EARP-THOMAS.

ANALYTICAL TESTING APPARATUS.

APPLICATION FILED APR-23.1917.

Patented Oct. 1, 1918.

Elm we nfoz OSWALD C. EARP-THOMAS, OF IBLOOMFIELD, NEW JERSEY.

ANALYTICAL TESTING APPARATUS.

Specification of Letters Patent.

"Patented Oct. 1, 1918.

Application filed July 23, 1917. Serial No. 182,340.

To all whom it may concern:

Be it known that I, OSWALD C. EARP- THOMAS, who have declared my intention to becomea citizen of the United States, residing at Bloomfield, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Analytioal Testing Apparatus; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to analytical testing apparatus; and it relates more particularly t apparatus for testing soils or other substances from which a gas is evolved upon treatment with a suitable reagent such as an acid.

The principal object of the invention is to provide a simple, compact and self-contained apparatus of simple, strong, and inexpensive construction which can be readily used by farmers and others as a soil tester, and by means of which a substantially accurate estimation of the amount of a constituent of the soil can be rapidly obtained, even though the user be entirely unfamiliar with analytical chemical methods. Another object is to provide apparatus of the foregoing general description which is relatively small in size and capable of being packed into small compass for transport, in the pocket, for example, and which is thus especially adapted for use in field work; 7

In its best form the apparatus comprises a reaction vessel or chamber provided with an appropriate closure adapted to seal the vessel against communication with the exterior except as hereinafter noted. The vessel closure is arranged to support within the vessel a reagent receptacle; and also to support gage means adapted to indicate the degree of pressure within the vessel. Such gage means may comprise a reservoir adapted to contain a supply of an indicating liquid, such as water, the reservoir being located inside the vessel and communicating by means of a suitable conduit or passage through the closure with 'a graduated water gage or index tube carried by and above said closure. The liquid supply reservoir does not open directly into the reaction ves sel but communicates therewith indirectly and in such manner that increase of gaseous pressure within the vessel is transmitted to the up er surface of the liquid in the reservoir, liquid being thereby forced therefrom into the graduated index tube before mentioned. In the best form of the invention, the arrangement of the gage means is such that upon charging the gage means with water or the like, preparatory to making a test, the liquid automatically assumes its proper starting or zero level.

In order to more fully explain the features of the invention and its mode of operation, certain desirable embodiments thereof are shown in the accompanying drawings, but these embodiments are to be understood only as illustrating the principles of the invention and not as restricting the invention to the specific constructional details shown. In these drawings:-

Figure 1 is an assembly view of one form of the apparatus in side elevation;

Fig. 2 is a central longitudinal section of the same;

Fig. 3 is a transverse section on the line 38 of Fig. 1; and

Fig. 4: is a partial view, in section, of a modification.

Referring particularly to Figs. 1, 2 and 3 of the drawings, 10 represents the reaction vessel which is here shown as an ordinary wide-mouthed glass bottle; a l-ounce bottle is very suitable, as a rule. The bottle is provided with a closure member 11, in this instance a rubber stopper fitting snugly within the mouth ofthe bottle 10. 12 is a liquid supply reservoir forming part of a pressure gage device. The reservoir may take the form of an ordinary short glass test tube, provided with a stopper 13. Through this stopper, and through stopper 11, a relatively small bore glass tube 14 extends upwardly fromnear the bottom of reservoir 12 into the bottom of glass gage or index tube 15, provided with suitable graduations 16 and constituting another part of the "gage device aforesaid. If preferred, the small tube 14 and index tube 15 may be made as a unit; but since it is usually desirable to interpose'between them a flexible connection in order to avoid breakage by rough handling, and since it is convenient to have the index tube readily disconnectible when not in use, a better plan is to form the index tube open at the bottom, as shown, and to use a closely fitting perforated rubber plug or stopper 17 to effect the connection between it and tube 14.

Surrounding reservoir 12, is another glass tube 18 of somewhat larger diameter, constituting a reagent receptacle, which may advantageously extend somewhat farther down into the reaction chamber than said reservoir and which is in direct communication with said chamber as by means of lateral opening 19. The reagent receptacle 18 may be held in proper position with respect to the reservoir 12 in any suitable manner. In the present example this is accomplished by means of rubber gasket 20 fitting snugly around the upper end of reservoir 12, and fitting snugly within the upper end of receptacle 18.

It is evident that there is no direct communication between the gage reservoir 12 and the reaction chamber in the vessel 10; but provision is made for connecting them indirectly in such manner that pressure within the reaction chamber is communicated freely to the upper surface of liquid 21 contained in reservoir 12. This may be accomplished in various ways, butthe arrangement here shown by way of illustration is a simple and effective mode of at training this result. A small bore glass tube 22 extends through the stoppers 13 and 11, and is here shown as terminating in a short bend at 23, above stopper 11, and adjacent the base of the index tube. By means of a detachable conduit such as a piece of'rubber tubing 24, the bend 23 is connected to the bent upper end 25 of another small bore glass tube 26 which extends downwardly through a suitable perforation provided in stopper 11 and leads into the annular space 27 between the reagent receptacle and the reaction vessel. This arrangement, while of course variable within the scope of the invention, has several distinct advantages. Thus, by rendering the pressure-transmitting conduit capable of being opened, as at the junction of rubber tube 2. and the upper end 23 of tube 22, an overflow means is provided whereby correct automatic leveling of liquid charged into the gage device is insured. The same object might be attained by use of a suitably located 3-way cock, for example, if a fixed conduit were preferred to the detachable rubber tube connection shown; but the present arrangement facilitates rapid disassembling and compact packing of the apparatus when necessary, and hence offers practical advantages.

From the foregoing description. it is apparent that in the particular construction explained, the stopper 11 carries attached to itself the complete gage means, and also the reagent receptacle; so that all these parts practically constitute a structural unit, removable as a whole from the reaction vessel or bottle 10. In the arrangement illustrated, the attachment of the specified parts to the stopper or closure 11 is frictional and is efiected directly or indirectly by means of the plug 13, washer 20, and tubes 14, 22 and 26.

In the customary mode of using the apparatus thus far described, the stopper 11 with all the parts attached thereto is removed from the reaction vessel and the sam-' ple 28, consisting of a known weight of soil or other material to be tested, is placed in the reaction vessel 10. \Vith the rubber tube 24 disconnected from tube terminal 23. water or any other suitable liquid is poured in at the upper end of index tube 15, and passing downwardly through tube 14, it fills the reservoir 12 and overflows at 23, the starting or zero level being finally established in tubes 1 and 22, approximately as indicated by the dotted line .r-JJ. Before or after the gage reservoir has thus been charged, the proper amount of dilute hydrochloric acid 29, or other appropriate reagent, is introduced into the receptacle 12 through the lateral opening 19. The stopper 11 is next crowded firmly into the mouth of the bottle, and the rubber tube 24 is finally slipped over the tube end 23, the apparatus then being in the condition shown in Fig. 3, and ready for the test to proceed. By tilting the apparatus sufiiciently, the acid 29 may be emptied into the reaction chamber and into contact with the sample 28. Assuming the latter to be a sample of soil containing calcium carbonate, for example, the result of the reaction between the acid and the soil will be an evolution of carbon dioxid gas. This tends to increase the pressure in the 10 reaction vessel, which pressure is transmitted by way of the described conduit means to gage. reservoir 12, the level of the water in the lattenbeing thus forced down, while the water escapes upwardly through tube 14 105 into the graduated tube 15, the Water continuing to rise in the tube 15 until the reaction in the bottle 10 is completed. The tube 15 may be of course graduated in any convenient units, but where the apparatus 110 is to be used as a soil tester it is generally convenient to graduate the tube to read in tons of calcium carbonate per acre. From the level attained by the liquid in tube 15, the operator can immediately read ofi on 115 the scale the degree of alkalinity of the soil sample in terms of the units employed in practice. He can thus ascertain in a very simple and expeditious manner just what the condition of the soil is in this respect and minal 23 until the cork ll is firmly seated,

narroiving the index, tube 15. *1; 1 1 a. It is 'OlJVlOllS that" various changes ca characterizing the I broad invention. :1 For Mreceptacle'mayibe combined in a unitary 1 phragmior partition 3l intoaan upper ireser- 1 voir for the: liquid 21, and :a lower reservoir ing 33 for 1 introducing; the'qreagent ;into the =tube communicati ngv with said reservoir and be g iarrang di to re e ve. l quid forwl J; therefrom, by. pressure developed in the rev t lonav ll lyi I. 5 Testing. apparatus.eomprising, in combination, a ,rezurtion vessel, a closure there or ,"a 'gagetube mounted on thejouter side n be i 1 lof said. closure, at kgage reservoir supported ma'de in the structural-*detail :ofithewapfrom the inner side of said closure within paratus withoutsacrificingmhe "advantages saidavessel ,and gbelow, said. gageltube, coni 1 duit means leadingaf rom .the lower, part of 3 the gage resenvoi z tothe gage tube, an over- ;fiow o' dlli eading from the ease r rv i t upwardly .to; a ,point of di'schz rge adjacent ,a the :lowertpart of said gage tube, and means ofor transmitting,gaseousgpressure from the v reaction, vessel togthe discharge 1 end of said the most part a But in any. ea se, the rubber -itubei 2 L should not he: slipped over the. terbecause otherwisew the. zliquid le'velw would be disturbed. Greater delicacy inlt'he gagereadings can obviously be obtained by example, the gage :reservoir. and the reagent structure" as shown Fi' 4, where- .a' single glass tube 3O 1 is d vided: :1 y means of a diao rfi u conduit 3. ;Te sting. apparatus comprising, in comreceptacle and discharging it therefromibe bination a reactiorrgvesselaa closure thereing provided as before. In this form of the for, ..l;iquidlevel age,means su ported by apparatus,moreover; thel'rubber} stopper 34; ;sa1d ,clofil rfiwi nd arranged ,to in icate presis simply reduced or shouldered at 35 for sures in said reaction vessel, and an overflow snug frictional engagement with tube 30,

for said gage means arranged substantially thus obviating the necessity for using a sepat the same level as the starting or zero level arate plug, such as plug 13 1n Flg. 2, to

on the gage. secure the depending reservoir to the stop- 4. Testing apparatus comprising, in comper. The construction illustrated in Fig. 4 bination, a reaction vessel, a closure therefor, has the advantage also of permitting the liquid level gage mean carried by said clouse of a wider diameter tube for the water sure and in operative communication with reservoir, with consequent increase in capacthe interior of the reaction vessel, and proity. This is especially useful where the samvision for permitting the gage means to ples to be treated run high in the constituent overflow when being charged with liquid to be determined.

and thus to automatically set itself at the In the foregoing detailed description, the proper starting level. parts have been referred to as constructed 5. Testing apparatus comprising, in comof certain specific materials, but it is to be bination, a reaction vessel, a' closure therefor, understood that these materials are mena liquid gage reservoir depending from the tioned merely as typical of materials ordiunder side of said closure and exposed to narily' most suitable for the purposes in the pressure existing in said vessel, a gage View, and that the invention is not limited tube surmounting said closure and arranged to the use of the particular materials in 'to receive liquid forced upwardly from said question.

reservoir, and a reagent receptacle substan- ,Wh th gage means and reagent retially coaxial with said reservoir and also ceptacle are referred to herein as supported depending from said closure. by or attached to the reaction vessel closure, Testing apparatus comprising, in comthis is to be understood in a broad sense as bination, a reaction vessel, a closure theredesignating any arrangement of the general for, a liquid gage reservoir depending from character involved in which the members or the under side of said closure and exposed parts in question are so attached to the cloto the pressure existing in said vessel, and sure, either directly or indirectly, as to be a gage tube flexibly mounted on the upper removable together as a connected whole side of said closure, said gage tube being from the reaction vessel. arranged to receive liquid forced upwardly What I claim is:

from said reservoir. 1. Testing apparatus comprislng, in com- In testmg -Pl-' the comblnatlon blnation, a reaction vessel, a closure therewith a closure member, of a reagent recepfor, a gage reservoir upported by id 1 tacle, a liquid reservoir, and an indicator sure within aid vess l but having n dir ct device communicating with said reservoir, communication therewith, a reagent recepall supported by said closure member. tacle opeiiing directlv into said reaction ves- 8. A soil tester comprising, in combinaseI and also supported by said closure, means tion, a bottle, a stopper therefor, a reservoir whereby gaseous pressure developed within ube supported wlthin the bottle from the said reaction vessel is communicated to said under side of saidgtopper and closed against reservoir, and a gage tube supported by said direct communication with said bottle, a closure outside the reaction vessel, said gage gage or index tube mounted on the upper 32 for acid or other reagent,,a lateralzopem for, a gage reservoir and a reagent receptacle both supported Within the bottle by said stopper, said reservoir being closed against direct communication with the inside of the bottle, but said receptacle opening directly into the bottle, a gage tube supported above the bottle by said stopper, 9. tube extending through said stopper and connecting said indicator tube with the lower part of said reservoir, an overflow tube leading from said reservoir through the stopper to a point adjacent the lower portion of the gage tube, and means whereby the outer end of said overflow tube maybe placed in free communication with the interior of the bottle.

10. Testing apparatus comprising, in combination, a reaction vessel, a closure therefor, a gage reservoir located within said vessel but having no direct eommunicationtherewith, a reagent receptacle opening into said a reaction vessel, means whereby pressure developed within said reaction vessel iscommunicated tosaid reservoir, and a gage tube supported outside the reaction vessel, said gage tube communicating with said-reservoir and being arranged to receive liquid forced therefrom by pressure developed in the re action vessel. a

In testimony whereof I hereunto afiix my signature. a a a i OSWALD o EARP-THOMAS. 

